Fireworks/Transcript
Transcript Text reads: The Mysteries of Life with Tim and Moby Fireworks explode in a night sky. Tim reads from a typed letter. TIM: Dear Tim and Moby, How do fireworks work, and how do they get to be different shapes, colors, and sizes? From, Rachel. Tim stands next to Moby who is wearing an Uncle Sam-style top hat. TIM: There are all kinds of different fireworks, with an almost endless variety of effects. MOBY: Beep. TIM: Well, actually, most of them just shoot sparks. MOBY: Beep. TIM: Yeah, but in a lot of different ways! Moby wears an American flag hat and stands next to Tim. TIM: The black powder used in fireworks is made up mostly of potassium nitrate, mixed with carbon and sulfur. An image shows a small pile of firework powder. Additional images show potassium nitrate, carbon, and sulfur molecules, labeled with their chemical names. Potassium nitrate is KNO3, carbon is C, and sulfur is S. TIM: It was discovered in China about 1,100 years ago. A map shows the location of China. TIM: Sparklers produce a bright burst of sparks and burn very slowly. Moby holds a burning sparkler. TIM: A wire is coated with a balanced mixture of fuel and an oxidizing agent like potassium nitrate to help it burn. An animation shows an unlit sparkler. TIM: The sparkler burns slowly from one end to another, rather than exploding like a firecracker. The tip of the sparkler ignites. The sparkling flame works down the wire as Tim describes the process. MOBY: Beep. TIM: Firecrackers? Well, black powder is wrapped in a tight paper tube. An animation shows black powder and a string fuse inside a red paper tube as Tim describes it. TIM: Lighting the fuse causes the tightly-packed powder to explode with a bang. The end of the firecracker's fuse ignites. The fuse burns down, and the firecracker explodes. TIM: The bright fireworks lights you see in the sky, or aerial fireworks, are sort of a combination of sparklers and firecrackers, propelled into the air inside small rockets, or launched out of a tube. An animation shows fireworks going off in a night sky. TIM: The firework has a lifting charge filled with black powder that burns like crazy when you light it, propelling it into the sky. An animation shows a firework rocket shooting into the sky. TIM: The powder lights a fuse, and when the firework reaches the right height, it explodes, releasing little packets of chemicals called stars. The rocket explodes in the sky, releasing chemical packets as Tim describes. TIM: The color of the fireworks depends on the chemicals mixed into the stars. When something burns, it gives off a specific set of frequencies of light. An animation illustrates a light wave. TIM: We see these frequencies as color. An image shows the seven colors of the visible color spectrum. TIM: Magnesium or aluminum for white, sodium for yellow, strontium or lithium for red, barium for green, copper for blue, and calcium for orange. With a dark sky as background, the names of each chemical powder appear in the color that powder produces. TIM: These stars burn like sparklers, filling the night sky with showers of sparks. An animation shows a display of fireworks in a night sky. TIM: Pretty. More complicated fireworks are made of multiple shells that burst at different points along the rocket's trajectory. They may also contain stars of different compositions to create different intensities and colors. An animation shows a rising firework rocket. It goes off as Tim describes. Two different sizes and colors of stars emanate from where the explosion happened. TIM: Some shells are full of explosives that make different sounds. Some crackle and whistle as the fireworks burst in the sky. An animation shows a display of fireworks. This time it is accompanied by booms, crackles, and whistles. MOBY: Beep. TIM: Oh, yeah, one thing we want to make sure you know is that fireworks can be really dangerous. Even the simplest sparklers can burn hundreds of degrees in temperature and cause serious burns. So don't ever use fireworks without an adult around. Moby adjusts a large cluster of fireworks, preparing to light them. TIM: I, uh, I guess it's okay if you're a robot. An animation shows a display of fireworks. It forms Moby's face and name in the sky. Tim laughs.